Respiratory System Chapter 9
Air Intake Air in the atmosphere is mostly Nitrogen (78%) Only ~21% oxygen Carbon dioxide is less than 0.04%
Air Intake Oxygen is required for Aerobic Cellular Respiration to produce ATP (energy required for life-processes) O2 is produced by plants through photosynthesis. O2 in the atmosphere must constantly replenished for human cells to survive.
Breathing vs. Respiration Breathing: the process by which air enters and leaves lungs
Breathing vs. Respiration Respiration: the exchange of oxygen and carbon dioxide 2 types: Internal Between cells in tissue and blood External Between airway and cells in blood Airway
Respiratory System - Structures Nasal Cavity Pharynx Epiglottis Trachea Larynx Bronchi Bronchioles Alveoli Diaphragm Rib Muscles Pleural Membranes
Respiratory System - Nasal Cavity Air enters through the nasal cavity 32oC Functions: - Hair filters out large debris 22oC - Mucus traps smaller particles - Sensory cells detect smells 37oC - Air is warmed and humidified
Respiratory System - Pharynx Pharynx: cavity at the back of the mouth - leads to the esophagus and trachea Trachea windpipe Epiglottis: flap that covers the trachea opening when swallowing food
Respiratory System - Larynx Larynx voice box Composed 2 elastic ligaments stretching across opening to the trachea = vocal cords
Respiratory System - Larynx The Larynx helps to: - Regulate breathing - Keep food out of lungs - Create sounds Thicker or swollen vocal cords produce lower frequency sounds
Respiratory System - Larynx Endoscopic views of the larynx Open - inhale Narrow - exhale Closed - sound
Respiratory System - Larynx The Larynx is also protected by the the thyroid cartilage The cartilage grows more in males than females = Adam s Apple
Respiratory System - Trachea and Bronchi Air from the trachea passes into 2 Bronchi (singular: bronchus) Trachea and Bronchi have cartilage rings to keep them open They are lined by cilia and mucus to keep pathogens out of the respiratory system
Respiratory System - Bronchioles The bronchi then branch off into smaller Bronchioles The Bronchioles do NOT have cartilage rings. Instead they have muscular walls. If the walls become inflamed (swollen) it becomes difficult to breathe Ex. asthma, bronchitis
Respiratory System Trachea Bronchi Bronchioles
Respiratory System - Alveoli The Bronchioles lead into numerous small sacs called Alveoli (singular: alveolus) The alveoli are extremely small and are surrounded by capillaries = site of gas exchange (external respiration) Alveoli during breathing
Respiratory System - Alveoli The inner surface of alveoli is lined with a layer of lipoproteins which prevents them from sticking closed when you exhale
Respiratory System
Respiratory System - Pleural Membrane Pleural Membrane: thin membranes surrounding the lungs and lining the inner surface of the chest cavity Stick the lungs to the chest wall so they move when the chest walls move as you breathe
Respiratory System - Pleural Space Pleural space: fluid-filled space between the pleural membrane and the chest wall Reduces friction between the lungs and chest wall If there is fluid buildup in the lung It becomes painful to inhale (lungs push on fluid and cannot expand fully)
Respiratory System PLEURAL MEMBRANE
Respiratory System - Lung Health Quitting smoking is the single best thing you can do to improve your health and quality of life. Non-smokers have a much lower risk of getting dozens of smoking-related diseases like lung cancer, heart disease, and COPD (chronic obstructive pulmonary disease, including emphysema and chronic bronchitis) From lung.ca E-cigarettes (vapes)
Respiratory System - Structures 1 12 11 2 3 4 5 6 9 7 10 8 Nasal Cavity Pharynx Epiglottis Trachea Larynx Bronchi Bronchioles Alveoli Diaphragm Rib Muscles Pleural Membranes
Respiratory System - Thoracic Cavity Diaphragm: thick muscle that separates the chest (thoracic cavity) from the belly (abdominal cavity) The lungs are surrounded by the ribs, sternum and Intercostal muscles
Respiratory System - Breathing The ribs are hinged to the spine - allowing them to move up and down Intercostal muscles control movement of the ribs External and internal muscles work opposite to each other
Respiratory System - Breathing Breathing (movement of air into and out of lungs) relies on differences in gas pressures. Atmospheric pressure remains constant but the pressure in the lungs changes as you inhale/exhale More volume = lower pressure Less volume = higher pressure
Respiratory System - Breathing Gases move from area of HIGH to LOW pressure Inhalation: Exhalation: Diaphragm contracts Diaphragm relaxes Chest volume increases Chest volume decreases Gas pressure in chest is low Gas pressure in chest is high Gas moves from atmosphere INTO lungs Gas moves into atmosphere OUT OF lungs
Respiratory System - Breathing When the external muscles CONTRACT they pull the ribs UP AND OUT When the RELAX the ribs fall DOWN AND IN (the external intercostal muscles contract/relax at same as diaphragm) Breathing video
Respiratory System - Breathing In a pneumothorax air fills the pleural space Air Collapsed lung
Respiratory System - Lung Capacity Normal lungs have a total air capacity of about 5L Lung capacity is affected by age, height, gender and health Lung disease, obesity and asthma are causes decreased lung capacity.
Respiratory System - Lung Capacity A Spirometer is used to measure Lung Capacity. Called a Pulmonary Function Test Not a recommended method
Respiratory System - Lung Capacity and Volumes A pulmonary function graph gives us the following information: TLC - Total Lung Capacity VC - Vital Capacity TV - Tidal Volume ERV - Expiratory Reserve Volume IRV - Inspiratory Reserve Volume RV - Residual Volume
Respiratory System - Tidal Volume Tidal Volume Tidal volume is normally ~500mL
Respiratory System - Pulmonary Function Graph Deep inhalation Deep exhalation
Respiratory System - Pulmonary Function Graph Tidal Volume - the amount of air that is exchanged in a Deep inhalation normal breath
Respiratory System - Pulmonary Function Graph Inspiratory Reserve Volume - amount of air that can be Deep inhalation inhaled forcibly
Respiratory System - Pulmonary Function Graph Expiratory Reserve Volume - amount of air that can be Deep inhalation exhaled forcibly
Respiratory System - Pulmonary Function Graph Residual Volume - amount of air that remains in the lungs Deep inhalation after exhaling (never is exchanged)
Respiratory System - Pulmonary Function Graph Vital Capacity - the total amount of air that can be Deep inhalation inhaled/exhaled
Respiratory System - Pulmonary Function Graph Total Lung Capacity Deep - total amount of air contained in the inhalation lungs
Respiratory System - Lung Capacity Predict how the Lung Volumes might be different in How would TLC, VC and RV change? Marathon runner (Athlete) vs. Smoker with Emphysema (Lung disease)
Respiratory System - Lung Capacity Average TLC 5 L Athletic TLC 5 L VC 3 L VC 4 L (increased) RV 2 L RV 1 L (decreased) Lung Disease TLC 5 L VC 2 L (decreased) RV 3 L (increased)
Respiratory System - Lung Capacity Graph the Pulmonary Function curves for these people: Normal: TLC 5L, IC 2L, ERV:1.5, RV 1.5 Obese: TLC 4L, IC 2L, ERV: 0.5L, RV:1.5L Note: IC = IRV + TV